CSU and DSU are layer1/2 devices. They simply take TDM channels at a mux/demux level. They have no knowledge of IP's/routing/gateways/etc. (Even though it may have an Ethernet interface, it's for management only or bridging at best)

You can find an old router on eBay, hook it up. You'll need computer with serial port to configure.

I can help you with config.

With the router, you'll have integrated CSU and routed connection to Ethernet port. Hopefully your ISP gave you a "LAN" range. With the LAN side, you plug in the "WAN/external" port of the LInksys firewall, then your computer(s) into the firewall.

If that's the one and your modem is indeed a modem acting as a bridge, all you need is to plug your router into the ethernet port on that modem and assign your static IP to your Linksys router.

The reason I started down this path was my company as T1 service too and a modem was provided to us with an ethernet connection. Since we have 5 statics as part of our service, I just simply wired a small switch to the modem and allowed the various servers and network devices we wanted on the internet.

The previous guy who was sort of put in charge of the company network made an assumption he also needed a router with a T1 CSU/DSU. The company purchased a Cisco 1841 with a T1 HWIC card which is now pretty useless because the ISP provided us with a modem negating the need for the router.

THIS THREAD HAS EXPIRED.
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